Absolutely stunning! They look to be in the façon de Venise style, which goes way back to the 16th century, but I guess these are a modern take on this style, given that they are signed in the way they are. I had a look through a book on the Cinzano Glass Collection, which has a lot of Venetian stemware, and there are numerous pieces with a similar look. The signature is indecipherable to me.